Black strips across roads

Surely they use the two strips to determine which way vehicles are traveling?

Calculating speed would be fraught with danger based on tyre pressures, tyre size etc all impacting the tyre footprint on the road and hence the time between hitting the two rubber hoses which appear to be no more than 1ft apart?

Dougal said :

Ok – I just thought about that for a minute and realised it could work as a speed checker if the two tubes were close and the tubes were recording the front tyre/s hitting the first tube, then the front tyre/s hitting the second. No need to worry about chassis length or the rear tyres.

Then, since you know the speed of the vehicle, and the amount of time between the two (or more) axles hitting the tube, you can calculate the wheel base of the the vehicles using the road. I don’t actually know if they bother to do this, but the maths is simple.

troll-sniffer said :

I used to think that was the case until I had a closer look one day and discovered that one end of the tubes seems to be planted in the ground. So I asked a nearby Ranger and he confided that they are in fact nitrogen fertilisers for nearby trees. Since air contains 70% nitrogen, a pressurised injection of nitrogen laden gas (air) to the roots saves on fertiliser. If you look at just about any of these installations you’ll see that there is usually a tree nearby, often in less than perfect condition. Just be glad your driving habits are contributing to the nation’s trees bit by bit.

Best answer ever.

Hahaha no I always speed and my conscience feels no guilt about it

Hahaha I bet you drive a black hatch and wear enormous sunglasses and have nothing to prove at all

Evil_Kitten said :

Dougal said :

But seriously, has anyone ever received a speeding fine this way?

If Snapper is correct and it was only used until the early 1990’s then that would only be people willing admit they’re really really old.

Anyone? 😛

I received an Amphometer fine in Captain Cook Crescent in 1987. Going 75 in a 60 zone. I wrote to the head of traffic services (pre self-government) claiming a lack of signage and the fine was withdrawn. I don’t think they’d be so lenient nowadays.

Evil_Kitten said :

I didn’t even think of this, but spot on! There are signs up saying the suburb is being resealed very soon!

Enjoy your CrapSealed roads. I wish they had left ours alone.

Evil_Kitten said :

Dougal said :

But seriously, has anyone ever received a speeding fine this way?

If Snapper is correct and it was only used until the early 1990’s then that would only be people willing admit they’re really really old.

Anyone? 😛

Willing to admit to being “really really old” (driving by 1990), but never booked like this.

Dougal said :

But seriously, has anyone ever received a speeding fine this way?

If Snapper is correct and it was only used until the early 1990’s then that would only be people willing admit they’re really really old.

Anyone? 😛

Dougal said :

Pardon my ignorance, but I don’t understand how could these tubes could record the speed of a vehicle if they can’t determine the chassis length? A motorbike, a ‘smart’ car, an average car, a bus – wildly different distances between the tyres.

I just always assumed that they were for counting purposes, and that perhaps tube two was a backup for tube one.

I used to wonder the same thing Dougal and the answer is very simple. They don’t need chassis length to calculate your speed. What they do need is two tubes placed a set distance apart, and the time it takes for your front wheel to pass between the two. Gives distance over time.

dks00k said :

A common use of these is to monitor traffic flow prior to re-sealing the road surface. This typically allows RTA / TAMS / Contractor etc to apply an appropriate amount of bitumen and aggregate for the traffic conditions.

Particularly with the warmer weather approaching its a fair bet if you have these in your street you will soon be able to drive by and flick stones up at oncoming cars and cyclists.

I didn’t even think of this, but spot on! There are signs up saying the suburb is being resealed very soon!

Ok – I just thought about that for a minute and realised it could work as a speed checker if the two tubes were close and the tubes were recording the front tyre/s hitting the first tube, then the front tyre/s hitting the second. No need to worry about chassis length or the rear tyres.

Nothing to see here… move along…

But seriously, has anyone ever received a speeding fine this way?

Pardon my ignorance, but I don’t understand how could these tubes could record the speed of a vehicle if they can’t determine the chassis length? A motorbike, a ‘smart’ car, an average car, a bus – wildly different distances between the tyres.

I just always assumed that they were for counting purposes, and that perhaps tube two was a backup for tube one.

A common use of these is to monitor traffic flow prior to re-sealing the road surface. This typically allows RTA / TAMS / Contractor etc to apply an appropriate amount of bitumen and aggregate for the traffic conditions.

Particularly with the warmer weather approaching its a fair bet if you have these in your street you will soon be able to drive by and flick stones up at oncoming cars and cyclists.

Sgt.Bungers said :

They’re “Pneumatic Road Tube Counters” which register vehicle axle movements.

As you’ve suggested, they’re used to count the number and types of vehicles using the road, as well as vehicle speeds.

I used to think that was the case until I had a closer look one day and discovered that one end of the tubes seems to be planted in the ground. So I asked a nearby Ranger and he confided that they are in fact nitrogen fertilisers for nearby trees. Since air contains 70% nitrogen, a pressurised injection of nitrogen laden gas (air) to the roots saves on fertiliser. If you look at just about any of these installations you’ll see that there is usually a tree nearby, often in less than perfect condition. Just be glad your driving habits are contributing to the nation’s trees bit by bit.

they often have a Near Field Communication or Radio Frequency ID capability built in, allowing the government to track everyone driving over them. It gets stored indefinitely in the 8 million square kilometre data centre that also stores all your GPS phone data and every call, SMS and email you ever made ever. EVVVERRRRRRRR….

*cue x-files music*

RandomPoster said :

If there is one, it is just for traffic volume and if there are two then it is speed also.

That makes sense. So what if there’s 4? This road has a set of 2 in one spot and another set of 2 a bit further along. I guess they’re just seeing the amount of traffic & speeds in 2 different spots?

There’s no point to point monitoring going on?

dpm said :

“Are they speed related in any way?”

Hahahaha! Someone got a guilty conscience?? 🙂

Hahaha no I always speed and my conscience feels no guilt about it 😛

there are a couple at intersections on Melrose Drive that are connected to cameras of some sort. I don’t think they’re the regular speed ones but you never know.

SnapperJack said :

This was the way cops used to issue speeding tickets before radar and speed cameras. It was called an Amphometer and was used until the early 1990s. The tubes would be laid across the road and further on the cops would be in a car monitoring the speed of cars passing over it. They would then flag down cars that were speeding and issue the drivers with speeding tickets.

My recollection is that amphometer strips used to be a lot further apart than the traffic counters we see.

Don’t have a problem with these traffic counters collecting approximate speeds, but I don’t think there’s any way they could be used for ticket-issuing. Determining camera/cushion placements … probably.

f4te said :

Sgt.Bungers said :

As you’ve suggested, they’re used to count the number and types of vehicles using the road, as well as vehicle speeds.

So slow down when you see them, otherwise they’ll put in more speed bump/cameras.

This.

“Are they speed related in any way?”

Hahahaha! Someone got a guilty conscience?? 🙂

This was the way cops used to issue speeding tickets before radar and speed cameras. It was called an Amphometer and was used until the early 1990s. The tubes would be laid across the road and further on the cops would be in a car monitoring the speed of cars passing over it. They would then flag down cars that were speeding and issue the drivers with speeding tickets.

Sgt.Bungers said :

As you’ve suggested, they’re used to count the number and types of vehicles using the road, as well as vehicle speeds.

So slow down when you see them, otherwise they’ll put in more speed bump/cameras.

If there is one, it is just for traffic volume and if there are two then it is speed also.

Sgt.Bungers said :

They’re “Pneumatic Road Tube Counters” which register vehicle axle movements.

As you’ve suggested, they’re used to count the number and types of vehicles using the road, as well as vehicle speeds.

And all the kids who jump on them.

They’re “Pneumatic Road Tube Counters” which register vehicle axle movements.

As you’ve suggested, they’re used to count the number and types of vehicles using the road, as well as vehicle speeds.